A highly studied pathogen-free flock of White Leghorn hens, now 2 to 5 years of age, will be categorized as to fertility and monthly plasma samples will be taken from each hen and stored. Since the incidence of spontaneous ovarian and oviductal tumors is well established for this flock, plasma samples will be available from hens of high and low fertility, those not laying eggs as well as those with carcinomas. The main objective is to identify any correlation between profiles with distinctive imbalances or ratios of steroid sex hormones in the plasma samples and development of either ovarian or oviductal adenocarcinomas. Hormones will be assayed by radioimmunoassay after chromatographic separation. Considering the number of cases available, distinctive patterns should emerge if hormones are a factor in etiology or progression of these adenocarcinomas. In addition, a method used to induce ovarian tumors in rats, i.e, irradiation, will be tried in hens and also sinistral castration. Since the histogenesis of ovarian carcinomas is unclear, both the spontaneous and induced tumors will serve to clarify the cell of origin and pattern of growth. Possible steroidogenesis of tumor cells will be examined. Since other types of carcinomas have been shown to secrete alpha-fetoprotein, presence of this antigen will be measured both in plasma of hens with carcinomas and in the tumor tissue. A possible etiology for ascites associated with cancerous peritonitis, leukolinins, will be measured in ascitic fluid and assessment of a therapeutic effect of an inhibitor of leukokinins will be evaluated in ascitic hens. These studies will provide information on the role of sex hormones in development of ovarian and oviductal adenocarcinomas and whether hormone profiles will serve as diagnostic and prognostic tests for these tumors. Another diagnostic test to be evaluated is that for alpha-fetoprotein. Importance of any lead developed in an animal model, with a high spontaneous incidence for diagnosis of human ovarian, oviductal or uterine carcinoma is obvious. Since this study will involve aged hens the first data will be forthcoming regarding epithelial tumors in fowl allowed to live out their natural life span.